Resilient Structures FAQ
Why build with natural materials?
Many families worldwide need inexpensive shelter. Often they can afford to work on building, but not to buy manufactured materials. Local natural materials are often the cheapest way to way to build. In addition, natural materials often also provide superior thermal comfort to conventional materials. Buildings that are passively climate-tempered will not require energy for climate control that these families cannot afford.
Why do traditional communities in different areas usually favor different types of natural building materials?
Vernacular housing usually is fairly well adapted to local climates and materials. Techniques are also chosen that are suitable to local skills and cultural skill sets.
Why use earth for building?
Subsoil used to build earthen buildings makes a non-toxic wall that is not subject to mold or decay (if kept dry) and has admirable thermal and humidity tempering qualities. If subsoil has enough clay particles of a strong enough consistency for the other particles, it holds together well.
Is it Possible to Estimate Soil Strength Quickly?
Aren’t high strength materials like Portland cement better than natural materials?
In many places Portland cement is too costly for laborers or unavailable. Although clay materials used as binders are weaker than cement, they can be strong enough for low-rise buildings when used carefully.
Shouldn’t every building be engineered?
That would be wonderful, but the poor who spend $300 on average on a home have no extra to pay an engineer. If builders learn basic guidelines, damages after earthquakes or floods will be less. Engineering design of model homes can help many directly and also by example.
Should natural materials be used in high-rise buildings in dense cities?
No, unless natural materials are manufactured, they will probably not be useful in high-rise buildings. High-rise buildings need higher compressive and tensile strengths and complex structural design that relies on uniform material performance. This blog focuses on the low-tech and low-skill techniques and will not discuss possibilities related to manufacturing.
Can stabilized earth be sustainable?If soil has enough compressive and/ or flexile strength, non-Portland chemical stabilizers may be cost effective if they are available.
Why not mix cement into natural walls?
Many builders of rammed earth or compressed earth blocks rely on stabilized soil to prevent decay from weathering un-stabilized or ‘raw’ wall materials. Since most natural walls are thicker than conventional brick or concrete masonry unit walls, using a proportion of chemical stabilizers can result in the use of a lot of stabilizer.
To create Portland cement requires seven times as much energy as to create lime. Cement can increase strength and also prevents damage from water. But cement does not always increase strength.
Compare the total Portland cement content of the wall volume before choosing materials. Natural walls without stabilizer can be protected by roof overhangs and/ or plaster or stucco, and will use less stabilizer than a solid stabilized
Does anything limit the use of fiber walls?
Lighter and softer wall materials made with large amounts of natural fibers need more maintenance than walls made of earth or stone. A culture that lacks habits and priorities for building maintenance should only consider fiber walls as temporary. Especially in hot, humid regions they are very vulnerable to damage by termites and other insects.
Should natural walls be reinforced with natural materials like bamboo and/ or wood?
In temperate climates termites can be controlled and damage limited by removing access tubes that are visible on wall exteriors. Ant pests in these areas do not nest in walls unless materials are damp enough to decay. But in hot regions, many species of termite fly, and nest high above the ground, and other insects that can damage walls are quite vigorous. Reinforcement is critical to safe building use. Economic pressures often cause buildings to be used with little or no inspection or improvement for generations. Natural reinforcements embedded in walls cannot be inspected to confirm that they are still performing a structural function.
Why is earthbag worth researching?
Builders appreciate this quick immediate construction process that can be reinforced by hammering steel rebar into walls without the need for pre-measured steel layouts in a high-precision foundation.
Earthbag’s barbed wire between every course provides fine-grained intrinsic tensile reinforcement that allows more flexure than most earthen wall materials, and gives earthbag walls great ductility. The containing fabric or mesh also contributes to delaying damage and preventing collapse as even broken segments of dried wall fill will